With the team’s fortunes in the dumps, it seemed one more blow to the storied franchise: A crafty thief, it appeared,had donned the oversized, fuzzy head of Wally the Green Monster and slipped out of Fenway Park, pulling off a caper that rivaled Theo Epstein’s great escape in a gorilla costume.

From Twitter user @OverMyUmbrella

A Red Sox employee wearing the costume posed with a fan in Copley Square while the search was underway.

Police units were dispatched to check out sightings: Boylston and Dartmouth streets, Downtown Crossing. Fans scoured the city, hoping for a glimpse of the pear-shaped monster.

When police finally caught up with the meandering mascot, it turned out the culprit was a Red Sox employee — with the most benign of motives.

“He decided on a whim to spread some good cheer around the city of Boston,” said a Red Sox spokeswoman, Zineb Curran.

The employee had been scheduled to roam the city in the Wally costume over the weekend, but in a burst of zealousness started a day early, walking and skipping around the city, posing for photos with fans, according to some news accounts. Those sightings caused something of a panic at Fenway, where employees, unaware it was one of their own, reported the mascot as missing to authorities.

Boston police described the perp as “green and furry, wearing a blue ball cap, white jersey with ‘97’ on the back, blue shorts and sporting a permanent grin to the face on an extremely large head.”

At about 4 p.m., a Fenway employee located the missing monster.

“Happy ending,” said Boston police spokeswoman Cheryl Fiandaca.

Curran would not identify the employee, who she said is in no trouble. “We wouldn’t reveal the mystery of Wally and who is behind the costume,” she said.

“At first we were hoping all of the commotion meant [Red Sox pitcher] Josh Beckett had been traded,” said Megan Eberle, a fan in her 20s
who was visiting the park with family. “Then again, we heard he broke out to spread Red Sox cheer, and us Sox fans could use some cheer.”